Light-sensitive silver halide photographic material

ABSTRACT

Graininess of a light-sensitive silver halide photographic material is improved by incorporating in any of the layers thereof a copolymer containing a n-vinylpyrrolidone unit with a mercaptotetrazole compound of the general formula,   WHEREIN R1, R2 and R3 are individually a hydrogen atom, an alkyl, alkenyl or alkynyl group, or an aryl or aralkyl group, and R2 and R3 may be same or different.

United States Patent [191 Sakamoto et a1.

LIGHT-SENSITIVE SILVER HALIDE PHOTOGRAPHIC MATERIAL Inventors: Kenro Sakamoto; Isamu Fushlki;

Fumio Shimizu; Katsutoshi Tozawa, all of Tokyo, Japan Konishiroku Photo Industry Co., Ltd., Tokyo, Japan Filed: Sept. 1, 1971 Appl. No.: 177,185

Assignee:

Foreign Application Priority Data Sept. 4, 1970 Japan 45-77072 US. Cl. 96/109, 96/1 14 Int. Cl G03c 1/34 Field of Search 96/109, 114

References Cited UNITED STATES PATENTS 5/1966 Cohen et a1. 96/114 Primary Examiner-Ronald H. Smith 5 7] ABSTRACT Graininess of a light-sensitive silver halide photographic material is improved by incorporating in any of the layers thereof a copolymer containing a nvinylpyrrolidone unit with a mercaptotetrazole compound of the general formula,

wherein R R and R are individually a hydrogen atom, an alkyl, alkenyl or alkynyl group, or an aryl or aralkyl group, and R and R, may be same or differem.

1 Clalm, N0 Drawings LIGHT-SENSITIVE SILVER HALIDE PHOTOGRAPHIC MATERIAL This invention relates to a light-sensitive silver halide photographic material improved in grainless of an image obtained by the development thereof.

It is well known that in order to improve a silver halide photographic material in graininess of the resulting image, the silver halide grains used in the photographic.

material should be made smaller in particle diameter. However, if a silver halide photographic material is made smaller in particle diameter of the silver halide grains used, the light sensitivity of the photographic material tends to be deteriorated accordingly, in general, causing the disadvantage that no desired sensitivity can be attained. With an aim to overcome such drawback, many efforts have heretofore been made by using specific chemicals or by varying the time and temperature for the preparation of silver halides, but no sufficiently satisfactory process has yet been found. Further, for the improvement in graininess of a lightsensitive silver halide color photographic material, there have been known a method in which the number of silver halide grains is increased, and a method in which a specific chemical is incorporated into the color photographic emulsion to lower the color developability thereof. However, the former method has such drawbacks that the expensive silver halide is required in large quantities, so that the photographic material becomes high in cost and, at the same time, the formation of fog becomes easy, while the latter method has such drawbacks that the effect of the chemical incorporated varies depending on the kind of coupler used, so that the coupler to be used in combination therewith is limited, or there is brought about marked desensitization.

We have found a novel process for improving graininess which process is entirely free from the abovementioned drawbacks of the prior art processes. Ac cording to the process of the present invention, it is possible to obtain a light-sensitive silver halide photographic material which has less tendency to fogging. without sacrificing the sensitivity and which has been greatly improved in graininess.

That is, the present invention provides a lightsensitive silver halide photographic material excellent in graininess which has been prepared by use of a silver halide photographic material incorporated with the combination of (I a poly-N-vinylpyrrolidone or a copolymer containing a N-vinylpyrrolidone unit and (11 a compound (hereinafter referred to as mercaptotetrazole compound") of the general formula (II),

1 1 1 o-srr it; N or I Examples of high polymers and mercaptotetrazole compounds usable in the present invention are shown below, though these are not limitative.

Examples of high polymers (I):

Monomer Compound ratio (l)l Poly-N-vinyl-Z-pyrrolidone (l)2 N-Vinylpyrrolidone/imidazolinoacrylic 42:58

acid amide copolymer (l)3 N-Vinylpyrrolidonelmorpholino acrylic 42:58

acid amide copolymer (l)4 N-Vinylpyrrolidone/piperidinoa-crylic 42:58

acid amide copolymer (l)S NNinylpyrrolidoneIZ-methylimidazo- 42:58

linoacrylic acid amide copolymer (l)(i N-Vinylpyrrolidone/acrylic acid 42:58

diethylamide copolymer (l)7 N-Vinylpyrrolidone/sodium acrylate 75:25

copolymer (l)8 N-Vinylpyn'olidone/methyl acrylate 42:58

copolymer (l)9 N-Vinylpyrrolidone/acrylic acid 75:25

amide copolymer' (l)l0 N-Vinylpyrrolidonelethyl acrylate 70:30

copolymer (l)ll N-Vinylpyrrolidone/acrylic acid 40:40:20

amide/ammonium malcamate copolymer (l)l2 N-Vinylpyrrolidone/acrylic acid 40:40:20

amide/maleic anhydride copolymer (l)l3 N-Vinylpyrrolidone/acrylic acid :20:20

amide/2-methylimidazole copolymer (l)l4 N-Vinylpyrrolidone/acrylic acid 3 60:20:20

amide/sodium 2-methylimidazole-3- hydropropionate copolymer (l)15 N-Vinylpyrrolidone/imidazole 60:40

imadazolinomaleamate copolymer (I)-] 6 N-Vinylpyrrolidone/2-methylimidazole 60:40

2-methylimidazolino-maleamate copolymer (I )-l7 N-VinylpyrrolidoneI2-methylimidazole 60:40

copolymer (l).-l8 N-Vinylpyrmlidone/morpholino- 20:20:60

methacrylic acid/methyl methacrylate copolymer (l)l9 N-VinylpyrrolidoneM-vinylpyridlino- 42:58

N-methyl iodide copolymer (l)20 N-Vinylpyrrolidone/piperidine 60:40

piperidinomaleamate copolymen (l)-2l N-Vinylpyrrolidone/thiourea half- 60:40

ammonium maleate copolymer (l)22 N vinylpyrrolidonelstyrene copolymer 70:30

(l)23 N-Vinylpyrrolidone/piperidino 20:20:60

methacrylate/methyl' methacrylate copolymer n-24 N-Vinylpyrrolidone/methacrylic acid 20:20:30

amide/methyl methacrylate copolymer (l)25 N-Vinylpyrrolidone/vinyl acetate 70:30

copolymer (ID-28 CHa5 n as Among the high polymers used in the present invention, all the copolymers containing vinylpyrrolidone can display marked graininess-improving effects when used in combination with the mercaptotetrazole compounds, though the degrees of said effects vary depending on the monomer ratios. nab If necessary, the above-mentioned high polymers and (HH; mercaptotetrazole compounds may individually be Q- CH1 used in the form of mixtures of two or more. The high polymer and mercapto compound may be incorporated into one emulsion layer, and may be incorporated not only into emulsion layers adjacent to each other but 11 -11 alsointo such auxiliary layer as sub layer, inter layer or -0CH a protective layer. These compounds may be incorporated into a silver halide emulsion at any step during the preparation of the silver halide emulsion, but it is w more effective to incorporate the compounds during the second ripening, or prior to coating, of the silver halide emulsion.

In case the compounds are desired to be incorpo- (II)13 rated during the second ripening of the silver halide emulsion, the temperature and time of the second rip- (IDM ening should be selected properly, whereby excellent photographic properties can be imparted to the resulting light-sensitive photographic material. In the case of gBjZ 7 a light-sensitive color photographic material using an (ID-17 -0HrC0OCrHs oil-soluble coupler, the compounds may be incorpo- (HHS 0,11, rated into the coupler dispersion. v

CHICHICHIN The amounts of the compounds to be incorporated 01H yary depending on the kinds of said compounds, but it 15 particularly effective to incorporate the high polymer D- in an amount of 0.2- to 100 g., and the mercaptotet- CH,OH: H:CH: aN razole compound in an amount of 0.001 to 10 g., per

0 H; mole of AgX. The high polymer is desirably one which is soluble in water or alkali. If the high polymer is not soluble in said liquid, it is dissolved in a solvent such as methanol, ethanol, acetone, ethyl acetate, dioxane, di-

l ll I methylformamide or the like, and the resulting solution is added to a silver halide emulsion or inter layerforming liquid. On the other hand, the mercaptotet- Compound R: R: razole compound may also be dissolved in the same (19.20 .41 manner as in the case of the high polymer, and the resulting solution is added to a silver halide emulsion or (ID-22 Q auxiliary layer-forming liquid.

The photographic emulsions used in the present in- CD43 3 vention include emulsions of AgCl, AgBr, AgClBr, Ag-

Brl, etc. These emulsions may have been optically sensitized with cyanine and merocyanine compounds, and may have been subjected to chemical sensitization treatments using sulfur-containing compounds, noble metal salts, polyalkylene oxide derivatives or reducing H 0 H3 0 compounds.

Further, formalin and the like may be used as hardeners, and synthetic surface active agents or natural surface active compounds, e.g. saponin and the like, may be used as coating aids. As couplers applicable tothe case of light-sensitive color photographic materials, there may be used those which can produce a color image by means of p-phenylenediamine type color developers. Examples of these couplers are yellow cou plers having benzoyl acetanilide groups, magenta couplers having a pyrazolone or indazolone nucleus or a cyanoacetyl group'and cyan couplers having a phenol or naphthol nucleus. These couplers may contain in the active methyleneor methine-portions a substituent capable of releasing by color development reaction such as, for example, halogens, or arylazo, aryloxy or arylthio groups. Further, these couplers may contain in the molecule either one or both of a non-diffusible group such as, for example, a long chain alkyl group or an alkylphenoxy group, and a water-solubilizing group such as, for example, a sulfonic group or a carboxyl group. Among these couplers, those which are oleophilic are dissolved in a high boiling organic solvent, e.g. dibutyl phthalate, or in a low boiling organic solvent, e.g. chloroform, acetone or dimethylformamide, and the resulting solutions are formed into dispersions. Further, water-soluble couplers are dissolved in alkali or the like, and the resulting solutions may be added directly to silver halide emulsions or incorporated into color developers.

In the case of the light-sensitive color photographic material of the present invention, the light sensitive layer may be composed of protective layer, yellow layer, yellow filter layer, magenta layer, inter layer, cyan layer, antihalation layer and support in this order from the upper-most layer, or may be composed of magenta, cyan and yellow layers in this order, though the order varies depending on the intended application of the photographic material. Further, the color developing layer may be composed of one or 2 layers.

As the support for use in the present invention, there is ordinarily used a paper or a natural or synthetic high polymer films of the cellulose acetate or polyester type.

In case the thus obtained light-sensitive photographic material according to the present invention is a blackwhite photographic material, it may be developed by treatment with a solution containing Metol, hydroquinone and phenidone, while in case the photographic material is a color photographic material, it may be developed by using a color developer of the pphenylenediamine type to form a color image directly by the first development, as in the case of a color negative, or it may be subjected to black-white development using Metol and hydroquinone and then to treatment for forming a color image, like the reversal color treatment.

Typical examples of the black-white developing agent used for development of the light-sensitive photographic material according to the present invention are hydroquinone, p-phenylenediamine, paminophenol, Metol, pyrogallol, amidol, glycine and l-phenyl-3-pyrazolidone. Typical examples of the color developing agent are sulfates, chlorides and sulfites of N,N-diethyl-pphenylenediamine, N-ethyl-N- hydroxyethyl-p-phenylenediamine, N-ethyl-N- hydroxyethyl-p-phenylenediamine, N-ethyl-N- hydroxyethyl-Z-methyI p-phenylenediamine and N ethyl-N-B-methanesulfonamidoethyl-3-methyl-4- aminoanil ine,

The present invention is applicable also to mixed packet type light-sensitive color photographic materials and DTR method light-sensitive materials.

The present invention is illustrated in further detail below with reference to examples, but the scope of the invention is not limited to these examples.

EXAMPLE 1 A high speed light-sensitive gelatinous silver iodobromide emulsion containing 3.5 mole percent of Agl and g. of gelatin per mole of AgX was subjected to second ripening, and incorporated with 0.18 g. per mole of AgX of a spectral sensitizing dye of the structure,

1- C2I5 C2115 to prepare a red-sensitive emulsions. This emulsion was incorporated with the high polymer (l)-l and the mercaptotetrazole compound (Il)-4in such a combination as shown in Table 1. Thereafter, two kinds of couplers of the structures shown below were subjected to a high speed rotary mixer to form a dispersion.

Coupler l Coupler (2):

GOCH:

In this case, the composition of the coupler dispersion was as shown below in which the amount of each constituent is per mole of AgX.

Formulation of coupler dispersion:

Coupler (1 16 g. Coupler (2) 4 g. 2,5-Di-(t)-octyl hydroquinone 0.5 g. Tricresyl phosphate 20 g. Ethyl acetate 30 g. 5% Alkanol B (trade mark of Du Pom.) 15 ml. 3% Gelatin 400 ml.

subjected to the following color development treatment:

(1) Color development, 20C., 12 minutes:

Formulation of developer:

Benzyl alcohol 3.8 ml. Anhydrous sodium sulfite 2.0 g. N-ethyI-N-fi-methanesulfonamidoethyl- 3-methyl-4-aminoaniline sulfate 5.0 g. Sodium carbonate (monohydrate) 50.0 g. Potassium bromide 1.0 g. Water to make 1,000 ml.

(Adjusted to pH 10.14 by addition of caustic soda or sulfuric acid) (2) Stop Bath, 20C., 4 minutes:

Formulation of stop solution:

(6) Water-washing, minutes. (7) Second fixing, 20C., 5 minutes:

Formulation of the fixing bath was same as in the first fixing bath. (3) Water-washing, minutes. (9) Drying.

The relative speed, fog and RMS graininess at the point of color image density value of 0.3 in the developed photographic materials were as set forth in Table l. (The RMS graininess referred to herein is a value of 1,000 times the standard deviation of variations in density value observed when a sample, which has been exposed and developed under definite conditions, is scanned by means of a microdensitometer having circular scanning openings of 2.5 p. in diameter.)

Table 1 Amount of high Amount of mercaptopolymer tetrazole compound Relaincorporated incorporated tive (g/mole AgX) (g/mole AgX) speed Fog RMS 100 0.16 81 (1)-1 4.5 g 103 0.17 78 (1)-19.0 g 100 0.16 78 (ll)4 0.006 g. 98 0.13 75 (ll)4 0.12 g. 93 0.10 75 (1)-l 4,5 g. (ll)4 0.06 g. 99 0.08 63 1 -1 4.5 g. tn-4 0.12 g. 96 0.08 54 (1)-1 9.0 g. (ll)-4 0.06 g. 98 0.08 58 (1)-1 9.0 g. (l1)-4 0.12 g. 95 0.06 51 From Table 1, it is clear that the photographic materials of the present invention are markedly low in RMS value without any substantial. desensitization, and thus have been greatly improved in graininess.

EXAMPLE 2 The red-sensitive emulsion used in Example 1 was mixed with a coupler dispersion of the composition shown below. The amount of each constituent of the coupler dispersion was per mole of AgX.

Composition of Composition of coupler coupler dispersion dispersion Coupler (2) 45 g. 45 g. Tricresyl phosphate 30 g. 30 g. Ethyl acetate 50 g. 50 g. Compound (ll)-l0 0.3 g. 3% Gelatin 300 ml. 300 ml. 5% Alkanol B 50 ml. 50 mlv High polymer (1)-5 10 g.

To the emulsion were then added, per mole of AgX, 120 ml. of 1 percent formalin and 300 ml. of 5 percent saponin. Subsequently, the emulsion was coated on a cellulose triacetate film base to a dry film thickness of 5 p, and then dried to prepare a light-sensitive photographic material. This photographic material was subjected to the same development treatment as in Example 1 to obtain the results set forth in Table 2.

Table 2 Relative speed Fog RMS Photographic material containing coupler dispersion (l) 0.13 88 Photographic material containing coupler dispersion (2) 101 0.11 65 From Table 2, it is understood that a marked graininess-improving effect can be attained also in the case where a coupler dispersion incorporated with the high polymer and mercaptotetrazole compound is added to a photographic emulsion.

EXAMPLE 3 Each of the two light-sensitive photographic materials prepared in Example (2) was exposed to a definite light and then subjected to reversal treatment using Kodak Process E IV-Kit (Trademark of Eastman Kodak Co.).

Reversal treatment conditions:

29.5C., 3 minutes 29.5C., 1 minute 1. Prehardening 2. Neutralization 3. First development 29.5C., 7 minutes 4. First stopping 29.5C., 2 minutes 5. Water-washing 27-32C., 4 minutes 6. Color development 29.5C., 15 minutes 7. Second stopping 29.5C., 3 minutes 8. Water-washing 2732C., 3 minutes 9. Bleaching 29.5C., 5 minutes 10. Fixing 29.5C., 6 minutes 27-32C., 6 minutes 29.5C.-, 1 minute 11. Water-washing l2. Stabilization The results of the reversal treatment were as set forth in Table 3, in which RMS graininess is a value measured at the point of a color density value of 1.0.

Table 3 Relative speed RMS Photographic material containing coupler dispersion (1 100 69 Photographic material containing coupler dispersion (2) 96 56 As seen in Table 3, a graininess-improving effect is clearly observed also in reversal color development treatment.

EXAMPLE 4 A highspeed light-sensitive gelatinous silver lOdObI'CF: mide photographic emulsion containing 5.0 mole percent of Ag], and 120 g. of gelatin per mole of AgX was subjected to second ripening, and incorporated with 0.20 g. per mole of AgX of a spectral sensitizing dye of the structure shownbelow and 1.8 g. per mole of AgX of 5-methyl-7-hydroxy-l ,3,4-triazaindolizine to prepare a panchromatic emulsion. Spectral sensitizing dye:

This emulsion was incorporated with the high polymer (l)-] 6 and the mercaptotetrazole compound (ll)-9 in such a combination as shown in Table 4. To the emulsion were then added, per mole of AgX, 100 ml. of 1 percent formalin and 200 ml. of5 percent saponin. Subsequently, the emulsion was coated on a cellulose triacetate film base to a dry film thickness of 4 u and then dried to prepare a photographic material. This photographic material was exposed through an optical wedge to a definite light and then subjected to the following black-white development treatment:

(I) Development, 20C., 9 minutes:

Formulation of developer:

Water 500 ml. Metol 1.5 g. Anhydrous sodium sulfite 100 g. Hydroquinone 3 g. Konigrain (trade mark of Konishiroku Photo industry C0., Ltd.) 2 g Potassium bromide 0.5 g. Water to make 1,000 ml.

(2) Fixing, 20C., 6 minutes:

Formulation of fixing solution:

Water 600 ml. Solution A Sodium thiosulfate 250 g. Water 200 ml. Anhydrous sodium sulfite 15 g. Solution B Acetic acid (23%) 58 ml. Konigrain 13.5 g. Potassium alum l5 g.

(The solution B was gradually added to the solution A with stirring, and the mixed solution was used as it was) (3) Water-washing, 15 minutes.

(4) Drying.

The results of the development were as set forth in Table 4, in whichthe RMS granularity is a value measured at the point of a density value of 1.0.

Table 4 Amount of Amountoi' mercaptohigh polymer tetrazole compound Rela= incorporated incorporated tive V (g/mole AgX) (g/mole AgX) speed Fog RMS 100 0.08 86 (Ii-l6 2 g. 10! 0.09 86 (II)) 0.08 g. 98 0.06 83 (ll-16 2 g. (ID-90.08 g. 98 .05 79 As seen inT able 4, the effect of thepresent invention is displayed also in the case of a light-sensitive blackwhite photographic material.

i 10 EXAMPLE 5 01511310 ours-@410 CHzCONH- To the emulsion were then added, per mole of AgX,

ml. of 1 percent formalin and 300 ml. of 5 percent saponin. Subsequently, the emulsion was coated on a cellulose triacetate film base to a dry film thickness of 5 p. and then dried to prepare a light-sensitive photographic material. This photographic material was exposed to a definite light and then developed at 20C. for 10 minutes with a developer 01? the following formulation:

Formulation of developer:

Anhydrous sodium sulfite 2.0 g. 4-Amino-N,N-diethylaniline hydrochloride 5.0 g. Sodium carbonate (monohydrate 50.0 g. Potassium bromide 1.0 g. Water to make 1,000 ml.

The results obtained were as set forth in Table 5. After the color development, the same treatments as in Example 1 were effected.

Table 5 Amount of high Amount of mercaptopolymer tetrazole compound Relaincorporated incorporated tive (g/mole AgX) (g/mole AgX) speed Fog RMS 100 0.l l 88 (l)-3 3 g. (ll)9 0.08 g. 96 0.09 76 (I)-5 3 g. (ID-9 0.08 g. 100 (M2 69 (l)-9 3 g. (In-9 0.08 g. 102 0.ll 71 (l)-20 3 g. (1l)-2 0.08 g. 95 0.07 t 68 (l)-20 3 g. (ll)-12 0.08 g. 98 0.11 70 (l)20 3 g. (ll)-13 0.08 g. 98 0.10 72 Asis clear from Table 5, the combination use of high polymer and mercaptotetrazole compound results in marked improvement in graininess.

EXAMPLE 6 A high speed light-sensitive gelatinous silver iodobromide photographic emulsion containing 4.5 mole percent of AgI, and g. of gelatin per mole of AgX was subjected to second ripening, and incorporated with 0.1 3 g. per mole of AgX of a spectral sensitizing dye of the structure shown below and 1.4 g. per mole of AgX of 5-methyl-7-hydroxy-l,3,4-triazaindolizine to prepare a green-sensitive photographic emulsion. Spectral sensitizing dye:

This emulsion was incorporated with a high polymer and a mercaptotetrazole compound in such a combination as shown in Table 6. Thereafter, a coupler (4) of the structure shown below was subjected to a high speed rotary mixer to form a dispersion.

Coupler (4):

The composition of the coupler dispersion was as shown below in which the amount of each constituent is per mole of AgX.

Composition of coupler dispersion:

Coupler (4) Tricresyl phosphate Ethyl acetate 5% Alkanol B 3% Gelatin g. 20 g. 250 g. 120 ml.

The above-mentioned coupler dispersion was mixed with the aforesaid emulsion to which were then added, per mole of AgX, 90 ml. of 1 percent formalin and 300 ml. of 5 percent saponin. Subsequently, the emulsion was coated on a cellulose triacetate film base to a dry film thickness of 5 p. and then dried to prepare a lightsensitive photoggphic material. This photograph ic ma terial was subjected to the same development treatment as in Example 1 to obtain the results set forth in Table 6.

Table 6 Amount of high Amount of mercaptopolymer tetrazole compound Relaincorporated incorporated tive (g/mole AgX) (g/mole AgX) speed Fog RMS (ll)4 0.02 g. (l)l 6 g. l0l 0.09 69 (ll)-l3 0.02 g. (l)8 3 g.

(ll)-22 0.04 g. 97 0.06 65 (l)3 3 g.

wherein R R and R are individually a hydrogen atom, an alkyl, alkenyl or alkynyl group, or an aryl or aralkyl group, and R and R may be same or different and wherein the N-vinyl-pyrrolidone polymer or copolymer is used in an amount of 0.2 g. to 100 g. per mole of silver halide contained therein and the mercaptotetrazole compound is used in an amount of 0.001 g. to 10 g. per mole of silver halide which material comprises a binder consisting essentially of gelatin and the polymer or copolymer of N-vinylpyrrolidone. 

